With the rapid development of semiconductor processes, low-profiled and compact-sized electronic components come to the market. Recently, it is popular in the art to integrate various mechanical components with electronic components to produce a nanometer scale product. Therefore, a micro electro mechanical system (MEMS) is developed, which involves manufacturing traditional mechanical components using a patterning method (such as exposure, development, etching, etc.) of the semiconductor manufacturing process to obtain miniaturized components. With these components converting environmental signals to electrical signals, signals are obtained by electrical conversion. These components are, for example, pressure sensors, flow sensors, accelerometers, gyroscopes, etc. MEMS has been widely applied in many fields, such as medical, automotive, mobile, global satellite positioning system (GPS) and so on. MEMS is a science that integrates electronic, electrical, mechanical, materials, chemical and other fields of knowledge that carries out a variety of microfabrication techniques using existing semiconductor technologies. MEMS elements can be provided on a chip surface, and encapsulated by a protective mask or underfill material, thereby achieving a MEMS structure. MEMS is also applicable in optoelectronics, communications and biotechnology fields. The miniaturization of electronic components significantly reduces the size of the electronic components, improves system efficiency, and reduces production costs. However, in contrast to the traditional semiconductor chips, surface components of the MEMS chip are easy to damage by environmential influence to cause reliability problem, so the cost of the MEMS package is about 50 to 95% of the overall production cost, thus the packaging of MEMS elements has become a technical bottleneck. With the current demand for miniaturization of electronic products, there is an urgent need for a package structure with a significantly reduced size.
Referring to FIG. 1, a cross-section view of a traditional semiconductor package 1 is provided. The semiconductor package 1 includes an MEMS chip 10, a cap 12, a semiconductor chip 14, an encapsulant 18 and a substrate 16. The cap 12 encapsulates the MEMS chip 10 to protect MEMS chip 10 from moisture, dust and other external environmental factors. A first wire 11a electrically connects a conductive pad 102 of the MEMS chip 10 and a first conductive pad 142 of the semiconductor chip 14. A second wire 11b electrically connects a second conductive pad 144 of the semiconductor chip 14 and a solder pad 162 of the substrate 16. However, the MEMS chip 10 and the semiconductor chip 14 are arranged side by side on the substrate 16, such that the volume of the encapsulant 18 cannot be reduced or meets the low-profile and compact-size requirements.
Therefore, how to overcome the shortcomings of the prior art is an important issue.